Road planer



, Feb. 2, v19443. IH. E. BoERMA v2,310,057I

ROAD PLANER Filed March 1o, 1941 F' D c hu Il INVENTOR HENRY E. BOERMA ATTORNEYS Patented Feb. 2, 1943 ROAD PLAN ER Henry E. Boerma, Cadillac, Mich., assigner to Pneu-Hydro Road Machinery Co., Cadillac, Mich., a corporation of Michigan Application March 10, 1941, Serial No. 382,619

2 Claims.

The invention relates to road Scrapers or planers of that type in which the scraper or planer blade is held into the work by fluid pressure. In the ,use of such machines it is frequently desirable to maintain the planer blade at a Iixed elevation, regardless of the character of the road bed or the material forming the surface thereof. The planer blade being moved downward by uid pressure, any change in the resistance of the roadbed would tend to cause either a raising or lowering of the blade, resulting in an undulation or irregularity in the planed surface. To avoid this eiect, it is necessary to provide restraining means for preventing the blade from moving downward below a predetermined point, and it is also important that this restraining means should be adjustable to permit positioning the blade at diierent levels.

It is the object of the invention to provide a means for positioning the blade, which is readily adjustable for diierent levels and which will not be rendered inoperative by the mud and dirt which frequently covers the working parts. To this end, the invention consists in the construction as hereinafter set forth.

In the drawing:

Fig. 1 is a perspective View of a planer embodying my invention;

Fig. 2 is a section through the planer blade and supporting beam, illustrating my improved means for limiting downward movement; and

Fig. 3 is a rear elevation showing the means for adjusting the restraining means for different levels of the blade.

In general construction, my improved planer comprises a beam A, preferably an inverted channel beam, which is adjustably secured to the sills B of a motor truck, to extend transversely beneath the same. The securing means comprises a plurality of members C clipped to the sills B and adjustably engaging threaded or corrugated shanks D extending downwardly therefrom. The lower ends of these Shanks are connected to arcuate segments E which in turn support the beam A so as to be adjustably secured about the center of the segments. The specic construction of this adjustable connection forms no part of the instant invention and therefore will not be described in detail.

The beam A is of a length suiiicient for the desired road work, so that its opposite ends extend a considerable distance to each side of the truck, beyond the sills B thereof. This provides .space for the location of a pair of fluid motors F which, as specically shown, includes cylinders F pivotally mounted between furcations ci bracket members F2 secured to the beam A and extending upwardly therefrom. Pistons. within the cylinders F are connected by piston rods F3, with rock arms G mounted upon a rock shaft H. This rock shaft is journaled in bearings l secured to the under side of the channel beam A and forms a pivotal or hinge mounting for a mold board J. Reiniorcing members K, mounted at their upper ends on the rock shaft H and attached to the mold board, complete the hinge connection. rlhus, when fluid under pressure is admitted to the upper ends of the cylinders F', it will move the pistons and rods F3 downward, which will swing the mold board J on the rock shaft H to press the planing edge'into the road bed.

To restrain the downward movement of the mold board and to hold the planing edge at a fixed level, I have provided the following means located at the opposite end portions of the beam A. L is a member secured to the beam, preferably by welding thereto, and having an upwardly and rearwardly extending flange L'. The ange L has a central slot L2 therein, open to the rear, and above this slot a ilaring recess L3. The slot L2 is of suiiicient width to receive a link M of a chain M', when turned parallel to the plane of said slot, while the recess L3 will form a bearing for an adjacent link M2 of the chain in a plane transverse to the plane of the link M. The lower end of the chain M' engages a member N which is welded or otherwise secured to the mold board J and is provided with a similar central slot N opening to the rear, and a similar aring recess Nz beneath said slot. A link M3 of the chain engages the slot N', while a lower link M4, arranged in a transverse plane, seats in the recess N2. A cotter pin O, passing through holes in the furcations of the member N and in rear of the link M3, holds the chain from acci dental disengagement.

With the construction as just described, the mold board may be adjusted to different levels by steps spaced from each other only by the length of one link of the chain. This is accomplished by slipping the chain link out of engagement with the slot L2 of the member L and reengaging another link with said slot. The fact that the flange L( extends upward as well as rearward avoids any danger of the chain becoming accidentally disengaged after it is once adjusted.

One great advantage of this construction is that the adjusting means is so readily accessible to the operator, being located near the ends o' the beam and beyond the frame and body of the truck. The construction is also one that can be manufactured at very low cost, including only the two members L and N, preferably castings, and a chain M of ordinary construction. There will never be any diiiculty in making the desired adjustment, even where all parts of the planer are coated with mud or dirt, for the chain link can always be easily disengaged from or engaged with the slot L2 in the flange L. The construction is also one which has a high degree of mechanical strength.

What I claim as my invention is:

1. In a road planer, the combination with a beam, a mold board hinged to said beam, and fluid actuated means mounted on said beam for pressing said mold board in a downward direction, of means for restraining downward movement of said mold board, comprising a pair of chains, a pair of members secured to opposite end portions of said mold board near the lower edge thereof, each of said members having a rearwardly opening slot for receiving a chain link and also having a recess on its under side forming a seat for an adjacent chain link, a cotter pin engaging an aperture in said member closing said slot in rear of the link engaged therewith, a pair of members secured to said beam, each provided with an upwardly and rearwardly extending flange slotted to receive another chan link and having a recess on its upper side for seating an adjacent link and constituting an anchorage for the chain, the pressure of said fluid actuated means normally holding said chain taut with said link seated in said recess.

2. In a road planer, the combination with a beam, a mold board hinged to said beam, and uid actuated means mounted on said beam for pressing said mold board in a downward direction, of adjustable means for restraining downward movement of said mold board comprising a pair of chains, a pair of lugs welded to opposite end portions of said mold board near the lower edge thereof, each lug having a rearwardly opening slot for receiving a chain link and also having a recess on its under side forming a seat for an adjacent chain link, a cotter pin engaging apertures in said lug to hold the chain link in said slot, a pair of members welded to the upper face of said beam at opposite ends and adjacent to the rear edge thereof, each member being provided with an upwardly and rearwardly extend ing flange slotted to receive another chain link and having a recess on its upper side for seating an adjacent link and constituting an anchorage for the chain, the pressure of said fluid actuated means normally holding said chain taut with said link seated in said recess.

HENRY E. BOERMA. 

